2 Answers
2

VS is backwards compatible, yes - you can open a VS 2005 solution file in VS 2008, for example. It's not forward compatible though - presumably that solution has been created by someone with VS 2010. EDIT: According to comments, with VS2010 SP1, you can open VS2012 solutions. I haven't verified this myself.

Fortunately, although the solution files aren't compatible, I believe you should be able to create a new solution in VS 2008 and add the existing project files created with 2010, so long as they haven't used any VS2010-specific features (either in the project structure or in the code itself). If the code targets .NET 4, you may need to adjust the project file to retarget it to .NET 3.5, too.

You may well see a warning about this (an unknown tools version, or something like that) - but it may very well work. I have a number of projects which have separate solution files for VS2008 and VS2010, but which use the same project files.

With only these 2 types of changes I was able to open the solution & projects with VS 2008. Of course other differences may appear but if you have time you can always use a try/fail method until you manage it.

this way I did a successful 2008 -> 2005 transition. I also had to modify the .vcproj file (an xml), the attribute from Version="9.00" to Version="8.00".
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naxaJul 28 '14 at 10:25

It would seem, provided you have backups, you can replace the .sln and .*proj files with the pre-problem versions of those files. After opening a VS 2003 project in VS 2008 and then trying to open it again in VS 2003, I changed one section in the *.sln file, namely from "Microsoft Visual Studio Solution File, Format Version 10.00 # Visual Studio 2008" to "Microsoft Visual Studio Solution File, Format Version 7.1 # Visual Studio 2003" But then I had to also replace the newer proj files with the old backups, which were "missing the 'VisualStudioProject' section."
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B. Clay ShannonOct 28 '14 at 18:27